采用Zemax软件设计出6镜片、数值孔径为0.06、2倍缩小、以405 nm半导体激光器为光源、分辨精度达5 μm、视场12 mm×12 mm 内波像差小于1/4波长、畸变小于0.005%的双远心投影光刻物镜的设计方法。将设计的物镜实物化, 并对其光学传递函数(MTF)作精确的实验测定, 利用所提出的MTF标准实验测量法, 得到该投影物镜的成像性能达亚10 μm线宽。

We introduced the design method of a 2× reduction projection lithographic objective with double-telecentric structure by Zemax optical design software, which uses the 405nm laser diode (LD) as the light source and has 6 lenses. Its number aperture is NA=0.06, the resolution approaches to 5 μm. In the field of view of 12 mm×12 mm, its wave-front aberration is less than a quarter of wavelength and the distortion ratio is no more than 0.005%. We also measured the accurate optical transfer function (MTF) value by experiments after the projection objective was fabricated. Through analyzing the noise disturbance law in MTF tests we got the conclusion that the projection objective has sub-ten micrometer resolution.